Use of Force in Self-Defence

Generally use of force by a state against another state is forbidden by Art2 (4) of the Charter. It prohibits use or threat to use force but Art 51 allows self-defence. It can include response to attack by non-state entities but it also has limitations ie hot pursuit. Because of those limitations on the right to self-defence it is interesting to analyse the extent of this right. 

Firstly, there are some terms important in the international law which need explanation. There is Jus ad bellum which is the law regulating right to use force and Jus in Bello where the law regulates the conduct of war. Definition of aggression is also important. It was defined in 1974 by the General Assembly as the use of force by one state against the sovereignty of another.

The use of force was allowed until 1945. It is because of a concept of just war expressed by Saint Thomas Aquinas which allowed force to be used in self-defence, in response to an attack. So, it was considered to be moral to protect itself and this moral justifications for a war are expressed in Jus ad Bellum. The moral conduct of the war is Jus in Bello. This view was also shared by Hugo Grotius. However, self-defence does not allow use of force on any occasion. Image result for self defence war

On the other hand, there is Art10 of the League of Nations Covenant 1919 which only encouraged states not to attack one another and to seek advice from the Council in case of an attack. But, a state under attack is unlikely to wait for a settlement. Therefore, allowing self-defence was necessary. It is considering the fact that Kellog-Briand Pact 1928 which renounced war rather than prohibit it also proved to be ineffective because of lack of sanctions and of right to self-defence. 

However, Art 1 of the UN Charter sets out that the purpose of the UN is to maintain international peace and security, to take effective measures for prevention of threats to peace and to suppress acts of aggression. Additionally, Art 2(4) of the Charter prohibits threat or use of force against another state. This article is regarded as a rule of Jus cogens or a peremptory norm from which no derogation is permitted except by a norm of a similar character. Therefore, any use of military force is prohibited. An example of this law in practise can be found in Nicaraqua v US where the US violated customary international law when it laid mines in Nicaraquan ports, attacked ports, oil installations and naval base. 

Nevertheless, one would argue that self-defence is a broad exception to Art 2(4) because of Art 5 of the 1949 North Atlantic Treaty which allows individual or collective self-defence in case of armed attack against one or more of the countries in Europe or North America. It is until the Security Council will restore international peace and security by necessary measures. However, Oil Platforms Case (2003) established that the use of force must be proportionate to the threat or force used against the country. 

Some states argue that it is proportionate to act when there is a danger of imminent attack which is ‘anticipatory self-defence’. For example, in 1981 Israel attacked the Iraqi nuclear reactor in Osirak because it directed its nuclear weapons towards Tel Aviv. However, surprisingly, Israel has been criticised by the Security Council. Although, it was clearly anticipatory self-defence. However, in another case of The Caroline Affair 1837 it was considered to be an anticipatory self-defence where the British authorities destroyed the US steam boat.

However, British Secretary of State Daniel Webster argued that Britain must demonstrate the ‘necessity of self-defence, instant, overwhelming, leaving no choice of means, and no moment for deliberation.’ This indicates that self-defence is not that broad exception. 

Pre-emptive strikes are another form of self-defence where a military action is taken in response to threat from another country to prevent that state from carrying out its threat which is very wide approach to self-defence. President George W. Bush expressed in 2002 his support to pre-emptive actions when necessary to defend liberty and to protect lives. 

There is also a wider use of self-defence where a state rescues or protects its citizens abroad from serious violation of their rights which is called ‘rescue mission’. For example, in 1976 Israel forcibly freed its nationals taken hostage by hijackers at Entebbe Airport in Uganda. However, a state may also act to protect its interests ie property within the territory of another state which may be called ‘reprisal’ if it is a response to an act contrary to International Law by the offending state as Naulilaa case (1928) established. For example, the USA carried out an attack on Iraq in 1993 to retaliate for an Iraqi plot to assassinate George H. W. Bush. This demonstrate how widely use of force can be performed. 

Nevertheless, as to how much force is permitted there are two views. One is a restrictive view that Art 2(4) forbids use of force in any circumstances and all use of force is unlawful. However, it allows use of force in self-defence and where it is authorised by Security Council. Another permissive view is that not every use of force is outlawed, for example, anything not covered by the articles which can include rescue missions. Based on this view Israel still applies previous customary law.

However, The Caroline (1837) shows that self-defence is not a broad conception because the use of force would only be allowed if there is no choice of means and no moment for deliberation. Besides, there must be a proportional response to an immediate threat. It can include response to an attack or threat of an attack against the state or its people in another state. 

Generally, unilateral use of force, where a state has no authorisation of relevant international bodies ie the UN Security Council is prohibited by Art 2(4). However, Art 51 of the UN Charter allowed attacked states to defend themselves either individually or collectively. There are again two views on how broad this exception is. 

The restrictive view is that this article supersedes customary international law and so an attack by another state is required to allow self-defence as established in Palestinian Wall Case (2004). However, Permissive view shared in Nicaraqua v USA (1986) shows very wide possibility of using self-defence. For example, it allows using force if there was a threat of attack by mercenaries, armed bands, groups such as terrorists.  Additionally, Sir Robert Jennings in Nicaraqua v US said that self-defence can be used in response to an attack which includes provision of arms with logistical or other support. However, Judge Schwebel disagreed with him. 

However, the Palestinian Wall case (2004) also expressed a possibility of using self-defence against non-state entities if the attack has been done with the actual or implicit knowledge of a state or if the state condones the act or acquiesced to the act. For example, Al Qaeda acted with acquiescence of the Taliban government so the terrorist attack on the USA would be deemed to have been committed by Afghanistan.

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